Strength training during pregnancy influences hippocampal plasticity but not body development in neonatal rats

To describe the effects of strength exercise practice during pregnancy on the offspring's development parameters: growth and motor performance, hippocampal neuroplasticity, and stress levels.

Pregnant Wistar rats were divided into two groups: sedentary and exercised rats. Exercised pregnant rats were subjected to a strength training protocol (vertical ladder climbing) throughout the gestational period. Male offspring's body weight, length, and head size were evaluated during the neonatal period (postnatal days [P]2-P21), as well as motor milestones during P0-P8. At P8, a set of male pups were subjected to global hippocampal DNA methylation, hippocampal cell proliferation, and plasma corticosterone concentration.

Offspring from trained mothers presented a transient change in body morphometric evaluations, no differences in milestone assessments, enhancement of cell proliferation in the dentate gyrus of the hippocampus, and decreased global hippocampal DNA methylation compared with the offspring from sedentary mothers. Furthermore, strength training during pregnancy did not change the corticosterone concentration of exercised mothers and their offspring.

These data indicate that strength training can protect offspring's development and could impact positively on parameters linked to cognitive function. This study provides a greater understanding of the effects of strength exercise practiced during pregnancy on the offspring's health.